Zoonotic risk of Campylobacter spp. in urban wild birds: Prevalence and antimicrobial resistance profiles in Istanbul, Türkiye.

Abstract

The aim of this study was to determine the prevalence of thermophilic Campylobacter species in urban wild birds living alongside humans in Istanbul, to determine the species distribution of isolated strains, and to characterize their antimicrobial resistance profiles. In this study, 150 fresh fecal samples from wild birds living alongside humans (crows and seagulls living along the coastlines, and pigeons living in tourist areas in the city center) were collected from various regions of Istanbul, Türkiye. For Campylobacter isolation, mCCDA agar was inoculated, and suspected isolates identified as Campylobacter spp. by biochemical tests were identified by PCR. The phenotypic and genotypic antimicrobial susceptibility profiles of the isolated strains were determined. When fecal samples were examined using conventional methods, Campylobacter spp. was isolated from 2/150 (1.33%). As a result of mPCR applied to DNAs obtained directly from the examination samples, 16 Campylobacter spp. were found in 15/150 (10%). 14 of these (93.3%) were identified as C. coli, and 2 (12.5%) were identified as C. jejuni. Campylobacter was detected in 11 of 127 pigeons (8.66%), while 10 (7.87%) were identified as C. coli, and 2 (1.57%) were identified as C. jejuni; Campylobacter was detected in 4 of 22 seagulls (18.18%), and all were identified as C. coli. When the sample collection regions were compared, the frequency of Campylobacter spp. was highest in Beyazıt Square (60%), followed by Küçükçekmece Beach (40%). As a result of antimicrobial susceptibility tests and PCR performed for the presence of tet(O), aphA-3 and gyrA genes, gyrA gene was found in both isolates, while tet(O) and aphA-3 genes were not detected. This study revealed that urban wild bird populations resident in Istanbul are a significant reservoir for thermophilic Campylobacter species and pose a potential public health risk.